.... What version psp do you have? If you have an unhackable and you try happy bricking yourself. If 3000 no don't even try, if 2000 run pspident and figure out if hackable then do same steps as a 1000, if 1000 recovery flasher to 5.00 m33-6 and upgrade to 5.5 gen

Well, you need to run chickHEN when in 5.03 OFW, and when that has enabled (you'll know when it has; but it'll probably take you about half an hour- it did for me!), you can then run the 5.50GEN-D installer. Then update to GEN-D2.